Roll changing device for a mill or a similar machine

ABSTRACT

A roll changing device for a rolling mill in which the assemblies of roll chocks include traverse components, such as a pair of longitudinally extending bars. The device includes symmetrically on the entry side and delivery side of the mill a rail matched with the traverse components. Each rail is displaced by an hydraulic cylinder and lifts the assemblies of roll chocks as a unit until the rails align with tracks arranged externally of the mill.

United States Patent Quehen Mar; 11, 1975 1 1 ROLL CHANGING DEVICE FOR AMILL OR 3,585,831 6/1971 A SIMILAR MACHINE 1651,67) 3/1972 3,698,22610/1972 [75] Inventor: Andr Quehen, Pontoise, France 3,733,37 5 1973[73] Assignee: SECIM, Courbevoie, France Primary ExaminerMi1ton S. Mehr[22] Flled' 1974 Attorney, Agent, or Firm-Daniel Patch; Henry C. [21]Appl. No.: 432,781 Westin [30] Foreign Application Priority Data [57]ABSTRACT Feb. 22, 1973 France 73.06229 A rc,ll changing device for ar0lllng mill in which the assemblies of roll chocks include traversecompo- [52] US. Cl. 72/239 nents, Such as a pair of longitudinallyextending bars [51] Illl. CI. BZlb 31/08 h d i includes symmetrically onthe entry Side [58] Field of Search 72/238, 239 and delivery Side f themill a rail matched with the traverse components. Each rail is displacedby an hy- [56] References cued draulic cylinder and lifts the assembliesof roll chocks UNITED STATES PATENTS as a unit until the rails alignwith tracks arranged ex- 3,171,304 3/1965 Sims et a1. 72/241 y 0f themill 3,312,096 4/1967 Stubbs et al. 72/238 F, 3,376,724 4/1968Wolfendale et a1 72/239 1 Clam, 2 D'awmg Pmmioum 1 1915 $869,898

sum 2 g 3 FIG. 2

ROLL CHANGING DEVICE FOR A MILL OR A SIMILAR MACHINE The presentinvention relates to a roll changing device intended for rolling millsof similar machines. It applies, more particularly, to the work rolls ofa 4-high mill, but may also find application for use with other machinesin which the working components are rolls between which passes a productto be transformed and which rolls are subject to wear and surfacedeterioration requiring frequent changing.

All the devices known for quick roll change of the rolls of a rollingmill consist of the extraction or introduotion in the roll stand of acomplete set of rolls equipped with their bearings and their chocks; therolls being placed one on top of the other. This moving as sembly(rolls-chocks) is traversed either by rolling or sliding.

Unless the devices are very complicated in design, it is required, forinstance, that the tracks on which the assembly (rolls-chocks) istraversed be located at a fixed elevation. This is the only way in whichthe moving equipment is connected by a simple mechanism to theextraction or introduction rig. Also, this is the only way for handlingof the roll to the roll shops which would allow for continuity of thetrack between the part located in the stand and that located outside thestand.

in summary, therefore, the difficulty comes from the fact that rollbodies wear and that, consequently, during their use the rolls and theirchocks are at variable elevations in the mill.

The present invention which allows for the solution of thesedifficulties applies to a mill or a similar machine including in a standat least two rolls mounted in their chocks, the rolls and chocks being amoving assembly to be changed and being designed with traversecomponents for sliding or rolling capable of supporting the assembly andprovided with means for maintaining a fixed distance between thecenterlines of each roll and the traverse components, the mill orsimilar ma chine including guide components arranged parallel to thecenterline of the roll and on the outside with regard to the chocks, andalso including means for displacement of the moving assembly, whensupported, on the fixed guide components.

According to the invention, the device, more particularly, includessymmetrically on the entry and delivery sides of the stand: a trackmovable parallel to the centerline of the rolls and having a formsimilar to that of the traverse components of the moving assembly,guides of the movable track in which said tracks are arranged parallelto themselves adapted to move from a resting position where they arecompletely retracted and a work position where they become the extensionof the fixed guide components outside the chocks; the track adapted tocome into contact with the traverse components of the moving equipmentat an intermediate position between its resting position and workposition, and means for displacing the movable tracks between their twoextreme positions, these means being capable of supplying enough forceto lift the moving assembly when the guides come into contact with thetraverse components of the assembly.

According to a special form of the invention the tracks and the means ofdisplacement of each movable track are tied to a separator supportlocated at the bottompart between the housing posts of the mill or similar machine.

According to another special form of the invention applied to a 4-highmill, the plane of displacement of each movable track is arranged on anangle with regard to the plane of the centerlines of the rolls; eachmovable track, therefore, passing above the bottom backup roll.

The invention will be. therefore, described with more details referringto a particular design given as an example and represented by theaccompanying drawings of which:

FIG. 1 is a simplified elevational view ofa 4-high mill equipped with adevice according to the invention; and

FIG. 2 is a longitudinal section through the mill shown in FIG. 1 inwhich the left part of the figure is a section A-A of FIG. 1; the rightpart of the figure is a section BB of FIG. 1.

Referring to these drawings, the mill consists of two housings l and 2in the windows of which are arranged, on one hand, a pair of chocks 4and 5 of the top and bottom backup rolls 6 and 7; on the other hand, apair of chocks 8 and 9 of the top and bottom work rolls l0 and 11. Thechocks 8 and 9 of the work rolls are displaceable inside the openings ofthe corresponding chocks 4 and 5 of the backup rolls. Roll balancecylinders 13 are located between each cooperative pair of the chocks 8and 9. The drive and operation side bottom checks 9 are connected at thebottom by two sleds 14 extended laterally beyond each of the housings 1and 2 as best seen in FIG. 2.

On the entry and delivery sides of the mill, separator supports 16 arefitted at the bottom part of the housing posts to which they are fixedby means of the bearing plates 17. As best shown in FIG. 2, theseparator supports 16 each support two guide boxes 18 arrangedsymmetrically about the centerline of the mill. Each box 18 includes asleeve 19 fitted with a bushing 20 in which slides a cylindrical post21. On each side of the mill, the two heads of the posts 21 are securedto a track or rail 22 fitted with a liner 12. The 23. and post assemblyforms a sliding assembly allowing for a parallel displacement of therail 22. It should, particularly in FIG. 2, be noted that the plane ofdisplacement of the rail 22 is arranged on an angle with regard to theplane of the centerlines of the rolls, but the liner 23 remains alwaysin the horizontal position. The moving assembly, thus composed, passesslightly above the bottom backup roll 7 as depicted by the dot-dashlines associated therewith in FIG. 2.

In the centerline of the mill, each support 16 includes an opening inwhich an hydraulic cylinder 28 is mounted and pivoted on the support 16on trunnions "24 fitted in well-known type bearings and represented onthe drawings in a simplified way. The rod 25 of the cylinder 28 isconnected to the rail 22 by means of bearing plate 26 in which a nut 27allows for the adjustment of the cylinder rod length.

When not employed for roll changing, the assemblies described above arecompletely retracted, as shown in the drawings. It is to be noted thatthese assemblies do not affect the normal operation of the mill.

During roll change, the top backup roll 6 is first raised by means ofits balance cylinder, not shown. Then, the roll balance cylinders 13between the chocks 8 and 9 of the work rolls l0 and 11 are used to bringthe center distance of the work rolls to a predetermined distance whichmay, for instance, be that of the corresponding center distance of apair of new rolls while the rolls are continued to be so maintained. Thecylinders 28 are pressurized, which raises the rails 22 towards thevertical centerline of the mill. The rails will first touch by theirliners 23 the bottom faces of the sleds 14, which elevation depends uponthe wear of the bottom work roll 11. As the strokes of the cylinders 28continue, the rail assembly and the work rolls-chock assemblies 8 and 9are raised. At the end of the stroke of the cylinders 28, the sleds 14fixed on the chocks are exactly in line with the fixed track 30 locatedoutside the mill, as shown in FIG. 1, while the bottom work roll 11 israised out of contact with the bottom backup roll 7.

In this position the centerlines of the two work rolls will be at afixed predetermined distance with regard to the fixed track 30. It isthen easy to hook the rolls to the extraction and introduction rig whichmay be of any well-known type, for instance, by hydraulic or aircylinder or by a cable and drum arrangement in which the extraction andintroduction mechanism may be located on either the drive side or theoperating side of the mill.

When, after extraction ofthe work rolls, it is required also to extractthe backup rolls, the assembly of the equipment described above isretracted to its resting position as shown in the drawings. It is to benoted that none of the components of that assembly will have to bedisconnected since it is completely independent of the backup roll-chockassembly. It is also to be noted that during the lifting stroke of theroll-chock assembly, the mountings of the cylinders 28 on the trunnionspermits it to avoid carrying the shear load generated by the weight ofthe rail and the roll-chock assembly.

It is obvious that the invention is not limited to the example describedabove, but it may also apply to other designs which will only differ indetail or the use of equivalent means. Therefore, the invention may beapplied with any method of extraction of the rolls and the slidingtracks described may be replaced by rolling tracks if the movingassembly were equipped with wheels as known. Also, the sleds 14 do notnecessarily have to be fixed to the bottom work roll chocks. In othermill designs such a sled may be located at the bottom of the legs of thetop work roll chocks; the bottom chocks are then allowed to slidebetween these legs and remain suspended during roll changing. This wouldbe another method of keeping the center distance between work rolls at afixed predetermined distance during the roll change operations. Finally,devices other than hydraulic cylinders and other arrangements than guideboxes can be employed, which arrangements will have the essentialfunction of providing for parallel displacement of the rails 22 byproviding a vertical force sufficient to lift the movable assembly ofthe work rolls and its chocks.

In accordance with the provisions of the patent statutes, l haveexplained the principle and operation of my invention and haveillustrated and described what I consider to represent the bestembodiment thereof,

I claim:

1. A roll changing device for a rolling mill,

a housing having a window for receiving at least two rolls mounted inchocks, said rolls and chocks constituting an assembly unit to beremoved from said housing,

said assembly unit including means for transferring said two rolls andtheir chocks out of said stand and also including means for maintainingfixed distances between the axes of rotation of said rolls and saidtransferring means,

means arranged externally of said window for guiding said assembly unitinto and out of said window,

rail means movable parallel to the axes of rotation of said rolls, soconstructed and arranged that their planes of displacements are set atan angle with respect to a plane passing through the axes of rotation ofrolls such that the rail means are passable above the lowermost roll ofsaid mill and in which said rail means have support means for supportingand guiding said transferring means while said assembly unit is withinsaid window,

means for guiding said rail means parallel to themselves between aninoperative position where the rail means are retracted and an operativeposition where the rail means assume a predetermined supporting andguiding relationship with said transferring means, the constructionbeing such that the rail means are brought into contact with saidtransferring means of said assembly unit at an intermediate positionbetween their inoperative and operative positions, and

means for displacing said rail means between said inoperative andoperative positions,

said displacing means capable of carrying said roll assembly unit whensaid rail means are brought into a supporting relationship with saidtransferring means.

UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No. 5,9,898 Dated March 11, 1975 Inventor (s) Andre Quehen It is certifiedthat error appears in the above-identified patent and that said LettersPatent are hereby corrected as shown below:

Column 21, line l-l, after the word "liner" the numeral "12" should bedeleted and 23 should be be inserted.

, same line, after "The" the numeral "23" should be deleted and the wordrail inserted.

Signed and sealed this 27th day of May 1975.

(SEAL) Attest:

C. MARSHALL DANN RUTH C. MASON Commissioner of Patents Attesting Officerand Trademarks FORM PO-lOSO (10-69) USCOMM-DC 60376-P69 u 5. GOVERNMENTPRINTING orncs: a 93 o

1. A roll changing device for a rolling mill, a housing having a windowfor receiving at least two rolls mounted in chocks, said rolls andchocks constituting an assembly unit to be removed from said housing,said assembly unit including means for transferring said two rolls andtheir chocks out of said stand and also including means for maintainingfixed distances between the axes of rotation of said rolls and saidtransferring means, means arranged externally of said window for guidingsaid assembly unit into and out of said window, rail means movableparallel to the axes of rotation of said rolls, so constructed andarranged that their planes of displacements are set at an angle withrespect to a plane passing through the axes of rotation of rolls suchthat the rail means are passable above the lowermost roll of said milland in which said rail means have support means for supporting andguiding said transferring means while said assembly unit is within saidwindow, means for guiding said rail means parallel to themselves betweenan inoperative position where the rail means are retracted and anoperative position where the rail means assume a predeterminedsupporting and guiding relationship with said transferring means, theconstruction being such that the rail means are brought into contactwith said transferring means of said assembly unit at an intermediateposition between their inoperative and operative positions, and meansfor displacing said rail means between said inoperative and operativepositions, said displacing means capable of carrying said roll assemblyunit when said rail means are brought into a supporting relationshipwith said transferring means.